The long-term goal of this translational research program is to develop an in-depth understanding of the events that protect neurons from stroke in order to improve neuroprotective therapies. Stroke is the third leading killer in the U.S. yet there is a paucity of interventions available to provide neuroprotection. However, powerful endogenous pathways exist to control CNS cell death. These pathways are exploited in a phenomenon known as ischemic preconditioning in which neurons exposed to a sublethal challenge are subsequently provided profound resistance. The pathways recruited during preconditioning could provide novel and potent defensive targets. The ability to regulate molecular constituents requires an in-depth understanding of the signaling systems that contribute to this protective pathway. We have previously determined that elements traditionally associated with cell death, such as production of reactive oxygen species, are required for preconditioning. Recent advances in our understanding of stress-induced signaling suggests that there may be a previously under-appreciated conserved pathway which underlies preconditioning. We have developed a powerful, accessible and reproducible paradigm to evaluate the contribution of intracellular signaling cascades to the expression of ischemic tolerance. In this system, primary cultures are exposed to subtoxic chemical ischemia which provides subsequent protection against excitotoxicity. The goals of this research program are: 1) to identify the kinase pathways activated by cell stress which contribute to ischemic preconditioning, 2) to elucidate the mechanisms by which blockade of ROS results in alteration in potentially protective cellular chaperones and 3) to clarify the role of protein degradation and determine which, if any, binding partners limit and/or alter the transcription and neuroprotective activity of HSP 70. These studies will provide novel insight into endogenous molecular events that can be exploited to enhance neuronal survival.